Created attachment 1209[details]
example faulty graphics output
In 2.13.1 and 2.13.1 pacthed graphics outputs have missing horiziontal and vertical instances (typically 1 pixel width, guess) when graduated colour plotted. See for example,
> require(grDevices) # for colours
> x <- y <- seq(-4*pi, 4*pi, len=27)
> r <- sqrt(outer(x^2, y^2, "+"))
> image(z = z <- cos(r^2)*exp(-r/6), col=gray((0:32)/32))
Similar for (lattice) levelplot, both colour surface and associated color.key, and other similar functions, e.g. polarPlot in openair.
(Don't see with 2.13.0 when reinstalled, also don't see in pdf outputs but do with some other outputs, e.g. jpg. Would guess this problem was in grid, but very much a newbie at this type of thing.)
Kind regards,
Karl

some additional information:
- white lines change randomly when resizing the window
- white lines are clearly visible in bitmat graphics produced with png() and jpeg() for instance. They are visible in printed png or jpeg output as well. This is new and did not occur in R-2.13.0
- pdf() and ps(): white lines are not visible in Acrobat, but light white lines are visible with other viewers such as in SumatraPDF or in GSview. This was already the case in R-2.13.0. In any case, no lines show up in printed outputs.
- When converting (with Imagemagick and gswin64) pdf or ps files obtained with pdf() or postscript() into png or jpeg, the resulting graphics also show up some light white lines. This was already the case with R-2.13.0.
Hope this may help.
Gilbert